Speedometer a little fast? - Toyota Nation Forum : Toyota Car and Truck Forums

#2! · 11-16-2009, 03:43 PM

Anyone know if this is normal?

Comparing with a GPS the speedometer seems right in line with the GPS until 45 MPH. Then after that it seems to be 2-4 MPH faster than the GPS. I always thought it might just the lag of the GPS whenever I had the chance to glance over at it.
Last night driving home I did an experiment where I reset the trip meter on both. When I got home the speedo was at 55.8 and the GPS at 55.1.

hill8570 · 11-16-2009, 04:04 PM

With stock tires, most speedos indicate a bit on the fast side. A couple mph over GPS sounds pretty normal to me.

ekopel · 11-16-2009, 07:55 PM

exactly as he said. If you don't have stock tire size though, you will see a difference.

flyeri · 11-16-2009, 09:24 PM

My daughter used my GPS and noted the same thing. Not sure if she looked at it below 45 but when the speedo reads 50 the GPS indicates 47. That spread is about the same at 60 also. The GPS is correct, I am pretty sure.

N35QU!K · 11-16-2009, 10:00 PM

Noticed the same thing in my family's new Sienna, indicated I was going like 83, but was actually going 80.

My Camry actually does the same too, but I did accidentally remove the needle at one point, but it consistently reads 3mph fast still, so I guess I put it back perfectly, more or less.

CROYCE992 · 11-17-2009, 01:43 AM

this is really interesting. I have about ~5mph discrepancy between my speedometer and GPS which estimates that im going actually slower. I tested this against a couple different speed traps with my GPS ready and the GPS and speed trap reading were the same... now I have 17" rims on my ride.. does that make a difference i wonder?

i always thought that maybe my car had lost this performance over the years. lol atleast it also makes sense why i never got a speeding ticket in my car at least.. not to mention my 80 in a 40 on my bike sad story

any way to correct this? not that i mind i know how to subtract 5 lol

edit: if its worth mentioning i have a Magellan Roadmate 1412

also does this mean my car has more mileage than the odometer says it has?

#2! · 11-17-2009, 09:18 AM

Quote:

Originally Posted by CROYCE992

also does this mean my car has more mileage than the odometer says it has?

I figure driving 50 actual miles my odometer will read 50.6. So I drive about 360 miles a week. That comes to 4.32 extra miles.
So about every year I get an additional 225 miles on the odometer that shouldn't be there.